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Derivative Instruments - Additional Information (Details)	2 Months Ended	12 Months Ended
	Feb. 28, 2018 MMBTU $ / bbl bbl	Dec. 31, 2017 MMBTU bbl
Crude oil | 2018 Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl)		13,675,000
Crude oil | 2019 Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl)		4,091,000
Crude oil | 2020 Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl)		279,000
Natural gas | 2018 Swaps
Derivative [Line Items]
Total notional amount of natural gas (in MMBtu) | MMBTU		7,665,000
Subsequent Event | Crude oil | 2018 Swaps
Derivative [Line Items]
Average floor price (in dollars per barrel / dollars per btu) | $ / bbl	56.16
Total notional amount of oil barrels (in bbl)	756,000
Subsequent Event | Crude oil | 2019 Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl)	2,400,000
Subsequent Event | Crude oil | 2020 Swaps
Derivative [Line Items]
Total notional amount of oil barrels (in bbl)	217,000
Subsequent Event | Natural gas | 2018 Swaps
Derivative [Line Items]
Average floor price (in dollars per barrel / dollars per btu) | $ / bbl	3.03
Total notional amount of natural gas (in MMBtu) | MMBTU	668,000

X

- Definition

The average floor rate on a group of price risk derivatives such as floors or collars. A payment or receipt is triggered if the market rate falls below the floor rate on the contract.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Nominal energy measure used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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X

- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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